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Many ancient legends and fairy stories show that man dreamt of flying even long ago, but it is only in our times that this dream has realised.
The first practical step taken towards aerial navigation was the invention of the balloon towards the end of the 18th century, closely following the discovery hydrogen gas. Navigation of the air by balloons might be compared to the navigation of the sea by sailing vessels before the invention of the steam ; for balloons were the sport of the winds. However, for over a hundred years after their introduction, no method of propelling or guiding a balloon was . They were not "flying" machines, but only "floating" machines.
The next step was the invention of the dirigible balloon, or airship, which Count Zeppelin proved to practicable at the beginning of this century. The "Zeppelin," as it was called, was a huge cigar-shaped balloon propelled by a motor engine and steered like ship. The Germans expected great things from their Zeppelins in the Great War, but they proved to be rather a disappointment, and, although they are still as passenger air-ships, the future is probably with the aeroplane.
The aeroplane has a different history and flies according to different principles. The balloon and the are "lighter than air" crafts that are lifted and kept aloft by hydrogen gas, whereas the aeroplane, or "heavier than air" craft, rises and flies due the resistance of the air itself. Just as a piece of cardboard, when thrown edge-wise, will skim through the air a long way, so the "planes" the aeroplane, when forced forward by the motor-driven screw, will raise and maintain the whole machine in the air. This is the real "flying machine," and has now reached a high state of perfection, although it is only a recent invention. Airmen now think no more of rising thousands of feet and hundreds of miles in the air than travelling over good roads in a motor car. Man's ancient dream of flying came true.
Already, the Atlantic Ocean been crossed by aeroplanes, and aeroplanes have flown around the world. There are already regular air services that transport mail and passengers, such as those between and Paris. In a few years, all the countries in the world will be linked together by regular air services as they are now by steamboats railways.